Three concentric conducting spherical shells have radii $r, 2r$ and $3r$ and $Q_1, Q_2$ and $Q_3$ are final charges respectively. The innermost and outermost shells are earthed as shown in the figure. Choose the wrong statement.

Calculate the amount of charge on the capacitor of $4\, \mu \text{F}$ in the given circuit. The internal resistance of the battery is $1\, \Omega$. (in $\mu \text{C}$)

Three identical capacitors $C_1, C_2$ and $C_3$ have a capacitance of $1.0 \mu F$ each and they are uncharged initially. They are connected in a circuit as shown in the figure and $C_1$ is then filled completely with a dielectric material of relative permittivity $\varepsilon_r$. The cell electromotive force (emf) $V_0 = 8 \ V$. First,the switch $S_1$ is closed while the switch $S_2$ is kept open. When the capacitor $C_3$ is fully charged,$S_1$ is opened and $S_2$ is closed simultaneously. When all the capacitors reach equilibrium,the charge on $C_3$ is found to be $5 \mu C$. The value of $\varepsilon_r = . . . . $

The potential of point $A$ is greater than that of point $B$ by $19 \, V$. What is the potential difference in volts across the $3 \, \mu F$ capacitor?

The numerical value of the charge on either plate of the capacitor $C$ shown in the figure is

Four capacitors are connected as shown in the figure. Their capacities are indicated in the figure. The effective capacitance between points $x$ and $y$ is (in $\mu F$)